The present invention relates in general to blood monitoring during cardiovascular surgery, and, more specifically, to a device for detecting emboli in the extracorporeal blood during on pump coronary bypass surgery.
When bypass is used during cardiac surgery, steps must be taken in order to avoid neurological injury. Neurological risks include reduced cognitive abilities and stroke. Emboli (i.e., air bubbles or particulates) entering the blood circuit from the heart, aortic walls or other areas can cause these problems if allowed to enter the brain during surgery. It is desirable to have a method of detecting the emboli in the cardiac perfusion circuit before it reaches the brain so that surgical technique adjustments can be made to reduce or prevent the emboli.
Transcranial Doppler systems are known for monitoring emboli entering the brain during surgery, but these systems do not detect emboli until after they have reached the brain. A system that detects the emboli earlier in the perfusion circuit would be desirable because preventive measures can then be put in place prior to the emboli reaching the brain. Besides localizing the site where emboli are entering the system (e.g., in the pump and/or at the surgical field), detection prior to entry into the patient may allow rerouting or deactivation of a blood circuit to prevent the detected emboli from reaching the brain.